Many fields of machine design provide applications for rotating shafts extending through a series of bearing blocks mounted either on fixed supports, or secured to various objects carried by the shaft. Bearing maintenance on these installations is usually a problem. Unless all of the bearing components are laterally separable, the removal and replacement of one that happened to be in the middle of the series obviously requires the dis-mounting of the shaft, at least to the position of the bearing unit that seems to be causing the trouble. Split bearing housings and bearing inserts have been used to reduce this problem, but installation and alignment remain time-consuming operations. One application of this problem that has proved to be particularly troublesome is the so-called "walking beam" conveyor. A series of parallel fixed beams is mounted on some convenient ground support, and a transverse line shaft usually is received in bearings mounted on these beams. Interposed between the fixed beams is a second set of beams supported by bearings also engaged by the line shaft. The shaft carries eccentric assemblies received in bearing housings mounted on these latter beams, so that rotation of the shaft generates an orbital movement of the beams bringing them to a level above the plane of the fixed beams, and then below it. Objects placed on a conveyor of this type are subject to cyclical movements in which they are briefly lifted above the plane of the fixed support and moved slightly over the top sector of the orbital movement, and then again deposited on the fixed beams to await the next cycle. Maintenance of the obviously large number of bearings involved in a conveyor of substantial size has presented the problem responsible for the development of the present invention.